Abrasive wheel



Feb. 13, 1951 A. s. TITCOMB 2,541,844

ABRASIVE WHEEL Filed July 12, 1949 3 Sheets-Sheet 1 O I J3 if? unnmuh wHum w n mnmlmi? mm 12 IN VEN TOR.

ATTORNEYS Feb. 13, 1951 I A. s. TITCOIMB 2,541,844

ABRASIVE WHEEL Filed July 12, 1949 5 Sheets-Sheet 2 IN VEN TOR.

05 466;? Jiepa/a/ Efcomb fill/0am ATTORNEYS.

A. S. TITCOMB ABRASIVE WHEEL Feb. 13, 1951 3 Sheets-Sheet 3 Filed July12, 1949 ATTORNEYS.

Patented Feb. 13, 1951 AI ENT OFFICE AB'RASIIVE Albert Sl1"epard;Titcomb, SouthWarrem-R. 1.,

Application. Julyi'12; 1949, Serial No. 104,254

10 C ms, 1.

This invention relates-to; an abrasive: grinding wheelzwhich iscomposed-of a p r -o spaced; abrasive surfaces.

Abrasive-grinding;wheelsgof this character have. heretofore beenconstructed ofa grindingr ment composed of abrasive material shaped likea hollow cylinder, knowntin' thetradeas an inverted cup. The sidesofthecup areoften made of segments each locking into-x the next segment orsometimes by segments with spaces in between with locking devices, tohold-the sides-of the cup to theupper base of the .grinding wheel bymeans of whatis known in the trade as the chuck. This. wheel-isintended-for operating. on a mountingat thebottom of a rotatingverticals-pindle on work fastened to amovable base-(eitherrotary orre.-ciprocative). and where. the revolving segments arepressed downward.againstthe. work.v It;is' also intended for apparatusonamoun-tingat oneend of a. horizontal spindle on.iworklfastenedv to, a reciprocatingtable so that the revolvingse'g. ments are. pressed against the work.When the wheel. is applied tothe work, chips of the work and. also. ofthe cutting wheel arefformed. by, re-. moval of the stock .of each. Thisremoved stock will load up or interfere with the efiicientcutting actionof the usual types. of wheels, the cutting efiiciency of a wheeldepending to a substantial extent upon the. elimination or removalof'this debris. Thus the particular shape of the block and arrangement.of the several blocks in'the.

wheel are therefore very. important from the standpoint of an efli'cientcutting wheel. It has been found that if'this loose stock is readilyremoved from the. grinding before'it becomes im-' bedded into thecutting surface of the wheel or segment, it is unnecessary to; dress thewheel as frequently as otherwise and even more often eliminatesrsuch'dressing entirely. This is because the loose stock fills in the crevicesthat is; loads the wheel so that the cutting edges of the rough surfaceare neutralized and forms a smooth uncutting wheel which causes heating,burning, and warpage of the work being ground. This friction, instead ofcutting action, often causes sufficient friction to throw the workoffthe magnetic chuck, generally used, sometimes with serious results.

One of the objects of this invention is to provide a grinding wheelwhich will have abrasive blocks of a shape which will be moreadvantageous than any shapes with which I am familiar for the purpose ofa moreeflicient and freer cutting action in any unit of time;

Another object of this invention is to provide'a grinding wheel which.although providing a faster outiand making more chips of: work whilevgrinding, the abrasive material will not wear away as fast and; thedebris. will not load up. and therefore} the wheel will. maintain its'efficiency for-a on r-time.

Another object ofrthis-invention isto provide-a shaping of abrasivefblocksso' that the chipswill V beiself removed efiiciently and: thusprevent-loading ofrtheiwheel Another obj ectof-thisinvention is toprovide abrasivev blocks which-will cause their: leading edgetohave anefficient plow actionwupon -the chips which; are formedto spread thechips: outwardly, and inwardly of the wheel as the cutting surface ofthe-blockadvances.

Another. object of; this invention. is to provide argrinding wheel whichwill run:-cooland f-ree of while providing... passage outwardlyforundesired removedmaterial,

Another. object .of thisiinvention is to provide a cutting wheel.having. the abrasive blocks so are ranged that the leading. edge ofonewill overlap the trailingedgeof the "other sothatsome abrasivesurface will be. continually in engagement with' the work, yet providefree way for debris to v be self removed.

Another object of the, invention is to. provide an adjustable built-inplate which may be actuated by a single screw to back up the abrasiveblocks and which may be adjusted so that the'block will r108 movedfurther out axially of the wheel as their wearing surfaces are used upto assure more complete'usage of the block.

Another object ofthis invention is to provide a plurality of differentsized-- wheels by utilizing in the plurality of wheels aunit abrasiveblock which will be ofauniform size-and shape, the arrangement beingsuch, generally, that more blocks will be used in a larger wheel than ina smaller wheel, thus decreasing the number of shapes required to coverdiiferent diameters of grinding wheels.

Another object of this invention is to provide a clamping means whichmay becommon in a 91 Another object of this invention is to provide asimple form of clamping means for holding each of the abrasive blocks inposition.

Another object of this invention is to provide a rapid yet dependableclamping means which may be actuated by a single screw for holding eachof the abrasive blocks in position.

Another object of this invention is to provide.

a coolant guide for directing the application of the coolant to alocation just in front of or to a proper part of each of the abrasiveblocks as it is rotated about the axial center.

Another object of this invention is to provide an abrasive block whichis so shaped that it will be prevented from tipping out of line whenclamped in position.

With these and other objects in view, the invention consists of certainnovel features of construction, as will be more fully described andparticularly pointed out in the appended claims.

In the accompanying drawings:

Figure 1 is a top plan View of the wheel with a portion broken away toshow the abrasive blocks and their relation one to the other;

Figure 2 is a side view or edge view of the wheel;

Figure 3 is a top plan view of one of the abrasive block holding unitsdetached from its mounting plate;

Figure 4 is an elevation of this unit alone showing its'positionrelative to its mounting plate;

Figure 5 is a section on line 55 of Figure 4;

Figure 6 is a view similar to Figure 5 but showing the parts shown inFigure 5 in a different relative position;

Figure 6a is a view similar to Figures 5 and 6 but showing the block ina position between the positions shown in Figures 5 and 6;

Figure '7 is a sectional View on substantially line l'! of Figure 4;

Figure 8 is a perspective view of the body portion of the block clampingunit;

Figure 9 is a perspective view of the second portion or jaw thereofwhich is movable relative to the body to hold the block in position;

Figure 10 is a perspective View of the inner side of the stop or segmentadjustment plate for use in holding the abrasive block or segment sothat the cutting surface thereof shall be at a further extended positionbeyond the clamping shoe in order to consume, or use it up to fulladvantage; and

Figure 11 is a perspective view similar to Figure 10, but looking at theother inner stepped or contact side thereof.

In proceeding with this invention, I have constructed an abrasive blockor segment of an elongated shape which will have pointed ends. Theleading pointed end will be so positioned in the wheel that the oppositeflaring edges from the leading end will have a plow action upon thechips and debris removed by the preceding segment. These blocks are allof the same size and shape for standardization and for grinding wheelsof different diameters, and I usually mount more upon a larger wheelthan on a smaller wheel in order to provide the size of grinding wheeldesired. The blocks may also be arranged in overlapping circular echelonrelation so that a continuous cutting surface is provided on the workthus preventing the opportunity for the stock being ground to rise, andat the same time pro viding necessary chip clearance between. Theoverlapping relation will be so spaced that the chips removed from thework may be thrown aside from the wheel by centrifugal force as well asby physical displacement of the plow action referred to above. Coolantis usually delivered at a location just inwardly of the circular cuttingannulus of the wheel and flows to the work surface within this annulus.The coolant usually is laden with chips or broken off abrasive particlesand settles on any horizontal surface just within the cutting annulus.In order to discharge ordirect the flow of the coolant, I have in somecases provided a shelf onto which the coolant is discharged, which shelfwill serve somewhat to collect settlings which are carried by thecoolant, and I have so shaped this shelf that it will have channels oropenings which will lead the coolant to a point just ahead of each ofthe leading ends of the abrasive blocks which are utilized; thusdirecting the coolant to the most efiective point and a location whereit will assist in removing debris which is formed by the cutting edge ofthe abrasive block.

The wheel comprises an annular mounting plate it as shown in Figures 1,2, 4, 5, and 6 provided with a strengthening or spacing rib it also ofannular form and of a radius less than the similar dimensions of theplate which extends upwardly from the clamp bodies. A member known as acoolant guide continues as at I! so as to provide a thin portion 58extending inwardly and from which there depends a skirt l9. This thinnerportion 8 with skirt !9 comprises the coolant guide. These portions areshaded in Figure 1. Although they are of a complex shape, this will bereferred to later to show how such complex shape serves to direct thecoolant to the location desired.

On the under surface of the annular plate l5 there is rigidly secured aplurality of abrasive block holders such as shown in perspective in thetwo complemental views Figures 8 and 9. The assembled units for holdingthe abrasive block are shown in Figures 3 and 7.

Each of these units comprises a shell or body 26 which is generally ofarcuate shape providing an inner surface 2| for supporting the abrasiveblock designated 22. The width of this body or shell which is to extendaxially of the rotating axis of thewheel is sufficient to give a goodbearing surface for the block. The strip of material 23 which forms thisbody has a smooth outer surface and the body as a whole is of agraduated thickness as may be seen by its edge 24 so that the requiredstrength may be provided. The body is essentially solid with recessestherein for purposes as will be hereinafter pointed out. One end of thebody is turned inwardly in the form of a hook 25 to provide a socket 26into which one end of the abrasive block 22 may be placed. The other endof this unit has a jaw 2! (see Figure 9) mevably mounted upon it so thatit may engage the other end of the abrasive block 22. This jaw 21 has amounting portion 28 and a hook shaped portion 29 which engages theabrasive block to be held.

The body 23 of the unit has one end reduced as at 39 to provide asliding surface or face for engaging thereduced strip or surface 3] ofthe portion 28 of the jaw, the part 32 being cut away while leavinganother spaced surface 33 to engage this surface 30 alon the lower edgeI301:

t offthejaw, a'; gieq e 3e is for'me'd' m the" be 3 9' and a'tongue"35'entrsthisgroov'e so that the opposite edges of the tongue willfbe'guided by the side walls of the groove. 1 This maintains'thmovement ofthe jaw'in a; desired 'wliich'it' shouldhavej and inorder that aw may bedrawn toward clamping position,

the j there is a 'threaddfbor'e 3 t prbviu uparallel with:

thetonguels'ee'l ig'. Ql't'o be'erigaged by'a screw 31 (see Fi'gi '7):passingthrouglropening 38in the may 23i (see Fig.1 8) and' actuatedbyits sunken hexagenal' socket head 391 by means" of a I-Ie'x. wrenchI Aece'ss' 4'9 afiords access thereto.

Anabrasive block 22 which has a periphery such as shown in Figure '7 orFigure 3 will be of an original height'as' shown in Figure 5 so that its1 upper end willen'gage the under surface 6'8 of the plate Hi;While'oneof its ends 6! will fit into the recess 25", as shown inFigures '7 and 8, while its other end 52 will be grasped by the jaw 2-7urged through the screw 3 l so as to grip it firmly i the holdin g unit.Suitable pads such aspaper, or gasket, or other textile fibrous material63' will be" provided on the blocks along the engaging surfaces of the"end portions and center outside of the block so that the pressure willbe applied through this cushioning means. The block, as will be observedin Figure 5, projects out beyond the unit 26 so as to provide a quantityof solid abrasive material for grinding purposes; however, as the workis operated upon, the grinding surface will be worn from the surface 65,shown in Figure 5, upwardly toward the edge of the clamping unit, and itis desirable 'that the abrasive block which has become worn :from useand of lesser axial dimension, may be :moved outwardly of the unit 213so as to present :for use additional abrasive material.

In order to support the abrasive block 22, at a position outwardly fromthat shown in Figure 5, I have provided a member 61 as shown inperspective in Figures 10 and 11, to act as a variable abutment shoulderto engage the inner end surface of the abrasive block. The body 23 isrecessed as at 58 so as to accommodate this member 6! in a position asshown in Figure 5 wholly within the member 23 so as to in no wayinterfere with the mounting of the abrasive block 22 when it is toengage the under surface of the plate !5. This member 6'! comprises anarcuate portion 69 from which there extends upwardly a strut E8 toengage the under surface of the plate 15. The arcuate portion 69conforms to the shape of the body 23 and may be completely housed Withinthe recess 68 while the strut 10 engages the under surface of the platei 5, as shown in Figure 5. The inner edge of this arcuate portion 69 iscut away at its lower edge H so as to provide an overhanging shoulder 12which when moved inwardly from the position shown in Figure 5 to theposition shown in Figure 6, provides a point of engagement for the upperedge 33 of the abrasive block, as shown in dotted lines in Figure 6,while when the member as r6? assist is" guidingthe serene i's'hiovedinwardlya further amount, the'end 15 of the member 'serves" as"anabutment forthe abrasive block now reduced" to" the size" 22 asshown'in'Fi'gure 6; A mounting'for this member is as follows: I

An" opening l5is provided from the outside to the'recess 68which'is'ithreaded for'the receptionof a plug 16 which is fixed in'thisopening and'is provided with a threaded .bo'r'eii for the'rec'eption of"a threaded stud 78' which is rotatably' mounted inthe shelffme'mber' 6?.This rotatablemounting is accomplished by means ofa'he'ad 79 on the-stud18'located'loosely in a socket 88 and' held between the surface 8'! ofthe member GT and a threaded cap 82 secured in a bore 83- through whichthe stud 18 is passed. Thisstud may be manipulated by means ofa sunkenhexagonal socket 84 in its end which is accessible from the outside ofthe holding unit and by this arrangement and a suitable T wrench tooltoturn'this stud; the member 5? may be moved inwardly to present eitherits shoulder l2 or its end M: as an abutment surface for the innerorupper end or the abrasive block 22 so that itmay be moved; in twosteps. outwardly from the holding unit to more fully use the abrasivema-- tenarin the block, before it is discarded. The surfaces 35 and 85of the variable abutmentmember are cut away to. leave only bearingportions 8? and as so as to provide dirt clearance which-nzightotherwise unduly retard the move' ment of this shoulder member. Othercutaways are as at'el (see Fig. 10:) and 92. These cutaway surfacesconnect withopenings 93 and M- so that the centrifugal forcewhich mighttend to force dirt about the member 61' will tend to: further force itthrough the openings 93 and 94 so that it may be discharged from thewheel.

In operation, th rib it of the plate i5 will be attached to somerotatingmeans shown in dotted lines in Figure 2 at 96 having knownperforations through which coolant will discharge downwardly andoutwardly so that it will engage the portions 18 shown in Figure-1. Asrotary action occurs, any dirt or grit in the coolant tending to collectalong the upper, inner surface of the coolant guide I1 and IS, thecoolant by reason of the openings or peculiar formation of the shelf I 8will provide spaces 9'! through which the liquid will descend so as tobe in a position just ahead of the leading end of the abrasive block 22so that it will better perform its action.

The abrasive block which I have illustrated may be of different shapes,but fundamentally will have an acutely angled leading end and preferably for reversability will also have the same shaped trailing end,although this is not necessarily so.

I claim:

1. A clamping device to hold an individual bonded abrasiv blockcomprising a body member having an end formed into a hollow V to receiveone acutely angled end of the block in a wedging action, a jaw, means tomove the jaw with relation to the body member toward and from the bodymember to bind the block of abrasive into such wedging action, and asingle tongue and groove joint between the upper and lower edges of saidjaw and body member to guide the jaw in its movement.

2. A clamping device as in claim 1 wherein a single screw in alignmentwith said tongue serves to move said jaw.

3. A clamping device as in claim 2 wherein said single screw isrotatable in said body and has threaded engagement with a hole in saidjaw.

4. A clamping device as in claim 1 wherein the single tongue is on saidjaw and a single groove is in said body member.

5. A clamping device to hold an individual bonded abrasive blockcomprising a base disposed at right angles to its axis of rotation, abody at right angles thereto, a jaw to hold an abrasive block betweenthe jaw and body and extending away from said base and a member having astep therein to provide an abutment intermediate its top and bottomedges and mounted in said body for movement radially inward at rightangles to said axis of rotation to be engaged by said block to space theblock from said base.

6. A clamping member as in claim 5 wherein said member provides an endabutment surface and may b selectively held in difierent positions tovariously space said block from the base.

7. A clamping member as in claim 5 wherein said abutment member isprovided with threaded means located Wholly radially outwardly of theabrasive block for movement of the member at right angles to said axisof rotation.

8. A grinding wheel comprising a plurality of individual bonded abrasiveblocks arranged in circular echelon relation each with a wedge shapedleading inner edge extending generally parallel to the axis of rotationand a guard presenting a horizontal lip with vertical channels for thedownward movement of the coolant at the locations adjacent each of saidleading edges.

9. A grinding wheel as in claim 8 wherein said wheel is annular and saidmeans comprises a horizontal guard to catch the coolant and direct itoutwardly and circularly, said guard terminating at intervals fordownward vertical movement of the coolant.

10. A grinding wheel comprising a plurality of individual bondedabrasive blocks held in a chuck arranged in circular echelon relation,each with a wedge-shaped leading inner edge extending generally parallelto the axis of rotation and 1 within the inner contours of said abrasiveblocks,

a coolant guide presenting a horizontal lip extending over the top andavertical skirt along the upper inner end and upper inner side of saidabrasive blocks, said contour of the skirt of said coolant guideproviding channels for the downward flow of the coolant to the innerleading edge of said block.

ALBERT SHEPARD 'I'ITCOMB.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 436,892 Harrington "Sept. 23,1890 524,572 Beckert Aug. 14, 1894 1,416,475 Knowls May 16, 19221,600,054 MacLaughlin et a1. Sept. 14, 1926 1,641,799 Brandes et al.Sept. 6, 1927 1,767,321 Skillings June 24, 1930 1,794,992 Stratton Mar.3, 1931 1,797,526 Hoagland Mar. 24, 1931. 1,892,434 Larsson Dec. 27,1932 2,102,919 Rusofi Dec. 21, 1937 2,476,334 Titcomb July 19, 1949

